Checked On Registry Database - USERINIT.EXE

Back about three weeks ago, in an effort to speed up my start-up on my computer, I ran Cleaner. It identified all the start up things. I went through one by one and disabled those that I had checked on a registry database. Unfortunately one of the first I disable was USERINIT.EXE.Now, as some of you may know, I can't login to my computer! I can power on, and try to log in, the windows attempts to load my preferences, and then logs out. Over the past several weeks, I have tried in vain to get some helpful suggestions on how to remedy the situation, but obviously my range of knowledge in dealing with this type of problem isn't strong enough to figure it all out. It was suggested by a friend that I just do a ffr, but quite frankly, I see that as a last ditch effort. I have files on the computer, that I really don't want to lose. And it seems that as I know what the problem is....there must be someway to fix it without going to the extreme. As my computer is 3-4 yrs old, my windows CD was only for SP1, and I don't think that would help....although I don't really know.